Exterior openings on the roofs of residential homes and multi-story building are used for a variety of purposes including exhausts vents or valves for dryers, bathroom fans and kitchen fans. Exterior openings may also be used as intake vents or valves for attic fans and dryers. Roofs are exposed to the elements and therefore regularly come in contact with precipitation, such as rain and snow, as well as wind and fog. In order to protect the interior of the home or multi-story building, the exterior openings must be covered in such a way so as to allow the intake and exhaust of air while preventing the entry of precipitation and wind.
One approach to this problem is a curved cover 100 for a roof opening 112 in roof 116, shown in FIG. 1. FIG. I is an illustration of a cross sectional view of a conventional cover 100 for an outdoor roof opening 112. The cover 100 comprises a curved, tubular element having a downward facing orifice 102 at first end 104. The cover 100 curves at section 106 and then straightens out at section 108, ending at orifice 130 on the second end 138. Also shown is a planar element 132 surrounding the brim of the orifice 130. It is shown that nails or screws 134, 136 are used to fasten the planar element 132 of the cover 100 onto the roof 116 so as to cover the roof opening 112.
FIG. 1 also shows rain drop 118 following a diagonal trajectory 120 towards the roof surface 116, as is typical when rain is accompanied by wind. The rain drop 118 impacts the roof 116 at point 114 causing the drop 118 to splatter in various directions. It is shown that one splatter element 122 travels into the orifice 102 of cover 100 and contacts the inner surface 110 of the cover 100. The water of splatter element 122 is then pulled downwards by gravity and trickles or slides down the inner surface of cover 100 into the interior of the building. This is detrimental to a structure, as water and humidity can have deleterious effects on building materials such as wood, concrete and drywall.
Also note that there is a direct path with no obstructions from the orifice 102 of cover 100 into the interior of the building. This is a drawback to the design of cover 100 since the exterior of roofs are often also exposed to animals such as birds, rats, mice, pigeons, possums, squirrels and other rodents. Because birds, rodents and other small animals often seek small volumes in which to live, hide, eat or give birth, the inner volume provided by cover 100 can be a welcoming environment for an animal. As a result, it is commonplace to find that small animals have taken habitat or died inside cover 100, thereby clogging up the orifice 112 of the roof and possibly causing bad odors to enter into the building. It can be difficult to remove a diminutive live animal from a small volume such as that provided by cover 100 and even more difficult to remove a dead or decomposing carcass from such as location.
A further drawback to the design of cover 100 involves debris such as leaves, branches, fruits, and seedpods that may travel into the cover 100 via a strong wind. It is not uncommon to find that debris has clogged the opening 112 of the roof 116 and prevented the intake or exhaust of air via the opening 112. It can be problematic to remove debris that has settled within the cover 100 and caused an obstruction.
Therefore, a need exists to-overcome the problems with the prior art as discussed above, and particularly for a more efficient way to protect a roof opening from precipitation, wind, debris and rodents while allowing the entry or exit of air.